===================================================================
--- original.js
+++ change.js
@@ -1,44 +1,46 @@
-/****
+/**** 
 * Classes
-****/
+****/ 
 //<Assets used in the game will automatically appear here>
 // Dart class
 var Dart = Container.expand(function () {
-  var self = Container.call(this);
-  var dartGraphics = self.attachAsset('dart', {
-    anchorX: 0.5,
-    anchorY: 0.5
-  });
-  self.speed = -10;
-  self.update = function () {
-    self.y += self.speed;
-  };
+	var self = Container.call(this);
+	var dartGraphics = self.attachAsset('dart', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
+	self.speed = -10;
+	self.gravity = 0.5;
+	self.update = function () {
+		self.speed += self.gravity;
+		self.y += self.speed;
+	};
 });
 // Target class
 var Target = Container.expand(function () {
-  var self = Container.call(this);
-  var targetGraphics = self.attachAsset('target', {
-    anchorX: 0.5,
-    anchorY: 0.5
-  });
+	var self = Container.call(this);
+	var targetGraphics = self.attachAsset('target', {
+		anchorX: 0.5,
+		anchorY: 0.5
+	});
 });
 
-/****
+/**** 
 * Initialize Game
-****/
+****/ 
 var game = new LK.Game({
-  backgroundColor: 0x000000 //Init game with black background 
+	backgroundColor: 0x000000 //Init game with black background 
 });
 
-/****
+/**** 
 * Game Code
-****/
+****/ 
 // Initialize score
 var score = 0;
 var scoreTxt = new Text2('0', {
-  size: 150,
-  fill: "#ffffff"
+	size: 150,
+	fill: "#ffffff"
 });
 scoreTxt.anchor.set(0.5, 0);
 LK.gui.top.addChild(scoreTxt);
 // Initialize target
@@ -48,25 +50,25 @@
 // Initialize darts array
 var darts = [];
 // Mouse or touch down on the game
 game.down = function (x, y, obj) {
-  var newDart = new Dart();
-  newDart.x = x;
-  newDart.y = 2732 - 100; // Start from the bottom of the screen
-  darts.push(newDart);
-  game.addChild(newDart);
+	var newDart = new Dart();
+	newDart.x = x;
+	newDart.y = 2732 - 100; // Start from the bottom of the screen
+	darts.push(newDart);
+	game.addChild(newDart);
 };
 // Update game every tick
 game.update = function () {
-  for (var i = darts.length - 1; i >= 0; i--) {
-    if (darts[i].intersects(target)) {
-      // Update score
-      score += 1;
-      scoreTxt.setText(score);
-      darts[i].destroy();
-      darts.splice(i, 1);
-    } else if (darts[i].y < -50) {
-      darts[i].destroy();
-      darts.splice(i, 1);
-    }
-  }
+	for (var i = darts.length - 1; i >= 0; i--) {
+		if (darts[i].intersects(target)) {
+			// Update score
+			score += 1;
+			scoreTxt.setText(score);
+			darts[i].destroy();
+			darts.splice(i, 1);
+		} else if (darts[i].y < -50) {
+			darts[i].destroy();
+			darts.splice(i, 1);
+		}
+	}
 };
\ No newline at end of file